I recently read the book God, Freedom, and Evil by the Christian philosopher Alvin Plantinga, and was rather impressed (though not persuaded) by Plantinga’s methodical analysis of the logical problem of evil. One of the primary arguments of the book is that the existence of evil does not preclude a Christian worldview. Plantinga’s presentation of his argument can be a little difficult to follow as it is fairly technical, however, William Lane Craig and J. P. Moreland offer a summary of his arguments in the book Philosophical Foundations for a Christian Worldview, which I think gives a fair but simplified version of Plantinga’s defense:
“… the logical version of the internal problem of evil holds that the following two statements are logically incompatible:
1. An omnipotent, omnibenevolent God exists.
2. Evil exists.
“…. There is no explicit contradiction between them. If the atheist thinks that they are implicitly contradictory, then he must be assuming some hidden premises that would serve to bring out the contradiction and make it explicit. But what are those premises? There appear to be two:
3. If God is omnipotent, then he can create any world that he desires.
4. If God is omnibenevolent, then he prefers a world without evil over a world with evil.”
(Craig and Moreland, 537-8)
Plantinga (and Craig and Moreland) proceeds to argue that these hidden premises (3 and 4) can be disputed, demonstrating that there is no logical incompatibility between the existence of God and the existence of evil (premises 1 and 2). Attacking hidden premise 3, Craig and Moreland continue:
“Plantinga opposes this version of the problem of evil with what he calls the free will defense. He argues that if it is even possible that creatures have libertarian freedom (even if in fact they do not), then the two assumptions made by the objector are not necessarily true… if libertarian free will is possible, it is not necessarily true that an omnipotent God can create just any possible world that he desires… God’s being omnipotent does not imply that he can do logical impossibilities, such as make a round square or make someone freely choose to do something. For if one causes a person to make a specific choice, then the choice is no longer free in the libertarian sense… Suppose, then, that in every feasible world where God creates free creatures some of those creatures freely choose to do evil… Thus it is possible that every world feasible for God which contains free creatures is a world with sin and evil.”
(Craig and Moreland, 539)
There is, of course, one limitation to this argument, which is the problem of natural evil, that is, evils that are caused by natural phenomena such as natural disasters. Since Plantinga’s solution to this problem is so surprising, I must quote him directly so as not to allow the suspicion that he is being misrepresented:
“What about natural evil? Evil that can’t be ascribed to the free actions of human beings? Suffering due to earthquakes, disease, and the like?… a more traditional line of thought is indicated by St. Augustine (p. 26), who attributes much of the evil we find to Satan or to Satan and his cohorts. Satan, so the traditional doctrine goes, is a mighty nonhuman spirit who, along with many other angels, was created long before God created man. Unlike most of his colleagues, Satan rebelled against God and has since been wreaking whatever havoc he can. The result is natural evil. So the natural evil we find is due to free actions of nonhuman spirits.”
Before pouring undue scorn on this rather far-fetched sounding idea, it is important to recognize that Plantinga is not suggesting that this is in fact the cause of natural evil, but rather merely demonstrating that there are possible causes for natural evil which could, at least in theory, undermine the logical problem of evil. As Craig and Moreland note:
“Admittedly, ascribing all evil to demonic beings is improbable, but that is strictly irrelevant here. All one needs to show now is that such an explanation is possible and that, as a consequence, the objector’s argument that God and evil are logically incompatible fails.”
(Craig and Moreland, 539)
One disagreement I have with Plantinga’s defense is that it requires that libertarian free will is possible, which Plantinga presumably believes to be a reasonable assumption. However, the idea that libertarian free will is logically possible cannot be taken for granted. In his book Free Will, the philosopher and neuroscientist Sam Harris argues that free will is conceptually incoherent because it would require humans to be in control of things that are clearly outside of our control, such as the unpredictable circumstances and mental processes that cause our behaviors.
“Free will is actually more than an illusion (or less), in that it cannot be made conceptually coherent. Either our wills are determined by prior causes and we are not responsible for them, or they are the product of chance and we are not responsible for them… No one has ever described a way in which mental and physical processes could arise that would attest to the existence of such freedom.”(Harris, 5-6, 13-14)
“…the idea that we, as conscious beings, are deeply responsible for the character of our mental lives and subsequent behavior is simply impossible to map onto reality.
Consider what it would take to actually have free will. You would need to be aware of all the factors that determine your thoughts and actions, and you would need to have complete control over those factors. But there is a paradox that vitiates the very notion of freedom—for what would influence the influences? More influences? None of these adventitious mental states are the real you.”
As the philosopher Michael Tooley notes, “One problem with an appeal to libertarian free will is that no satisfactory account of the concept of libertarian free will is yet available… Some philosophers, such as Timothy O’Connor and Randolph Clarke have claimed that such an account can be given, but their suggestions have not been widely accepted.”
On a few occasions, I have had the opportunity to ask defenders of Plantinga’s free will defense to explain what precisely libertarian free will is and how it works. None so far have been able to come up with an explanation that they or I found satisfying. I tend to be persuaded that libertarian free will is not possible, and would therefore argue that libertarian free will is not on the table as a defense against the logical problem of evil (at least until it is demonstrated to be conceptually possible). As Plantinga, Craig, and Moreland point out, God cannot necessarily do something that is logically impossible. I would submit that libertarian free will is not logically possible, and therefore is not a reality that God could actualize.
Craig, William Lane, and Moreland, J. P. Philosophical Foundations for a Christian Worldview (IVP Academic, 2017).
Harris, Sam. Free Will (Free Press, 2012).
Plantinga, Alvin. God, Freedom, and Evil (Eerdmans, 1974).
Tooley, Michael. “The Problem of Evil”, The Stanford Encyclopedia of Philosophy (Winter 2021 Edition), Edward N. Zalta, URL = <https://plato.stanford.edu/archives/win2021/entries/evil/>.